|Power requirements and choice of an optimum frequency for a world-wide standard-frequency broadcasting station (Volume 63D) - Watt, A.D.|
Journal of Research of the National Bureau of Standards
Keywords: power requirements; optimum frequency; worldwide standard-frequency broadcasting station; atmospheric noise level; radiated power
|BBC Research and Development Report 1956-20 : The Neumann electrostatic microphone Type KM.54 - W.I. Manson, J. Nash|
R&D Report 1956-20 : The Neumann electrostatic microphone Type KM.54. W.I. Manson, J. Nash The Nuemann KM.54 is a small electrostatic microphone with nominally cardioid characteristics. Tests were carried out on a single specimen and the results of measurements of frequency response, sensitivity, noise level and susceptibility to magnetic fields are given in this report.
Keywords: microphone; frequency; output; shield; cardioid; axial; response; frequencies; voltage; impedance; electrostatic microphone; low frequencies; noise level; microphone head; microphone type; sound incident; frequency characteristics
|BBC Research and Development Report 1954-39 : The Nordwestdeutscher Rundfunk-Hiller electrostatic microphone Type M59 - J.R. Chew, D.E.L.Shorter|
R&D Report 1954-39 : The Nordwestdeutscher Rundfunk-Hiller electrostatic microphone Type M59. J.R. Chew, D.E.L.Shorter The M 59 is an electrostatic microphone of exceptionally small size and of nominally cardioid polar characteristics. Tests on a single specimen are described in this report. Frequency characteristics and figures for sensitivity, noise level and interference from magnetic fields are given, together with the results of a listening test.
Keywords: frequency; microphone; electrostatic; baffle; sound; interference; magnetic; characteristics; cardioid; output; microphone head; axbt microphone; frequency characteristics; noise level; electrostatic microphone; microphone type; sound incident; magnetic fields
|BBC Research and Development Report 1954-40 : The Telefunken microphones Type Elam 200 and Elam 201 - W.I. Manson, D.E.L. Shorter, H.D. Harwood, J. Nash, R.J. Packer|
R&D Report 1954-40 : The Telefunken microphones Type Elam 200 and Elam 201. W.I. Manson, D.E.L. Shorter, H.D. Harwood, J. Nash, R.J. Packer Tests have been carried out on specimens of the Telefunken electrostatic microphones type ELAM 200 and ELAM 201. The ELAM 200 microphone is pressure-operated while the ELAM 201 can be switched to give either omnidirectional or cardioid characteristics; identical pre-amplifier arrangements are used for both types...
Keywords: elam; blam; microphones; sensitivity; microphone; omnidirectional; cardioid; frequency; transformer; impedance; noise level; magnetic fields; type elam; electrostatic microphones; frequency characteristics; output transformer; microphone type; sound level
|mit :: ai :: aim :: AIM-1567|
From the bitsavers.org collection, a scanned-in computer-related document.mit :: ai :: aim :: AIM-1567
Keywords: model; mme; parameters; experts; markov; models; movement; contact; algorithm; transition; movement models; markov chain; prior knowledge; transition probabilities; movement model; training set; learning algorithm; noise level; input noise; test set
|BBC Research and Development Report Number 1987-21|
R&D Report 1987-21 : The assessment of the sound insulation requirements for a large broadcasting studio, using a scale model: Practical details. E.W. Taylor The techniques used in carrying out the assessment of relative levels of road traffic noise at the surfaces of a large building, using a scale model, are described. The results of such an assessment on a 100:1 scale model of a proposed new building at the BBC Television Centre are considered...
Keywords: sound; source; noise; studio; wall; exposed; pressure; level; measurements; bbc; sound field; scale model; sound pressure; noise sound; pressure level; exposed wall; polar diagram; traffic noise; sound source; noise level
|mit :: lcs :: tr :: MIT-LCS-TR-406|
From the bitsavers.org collection, a scanned-in computer-related document.mit :: lcs :: tr :: MIT-LCS-TR-406
Keywords: noise; ecg; beat; unknown; data; aristotle; interval; calvin; annotation; noisy; electrode motion; data processor; noise level; annotation file; noisy ecg; situ mode; noisy data; human expert; knowledge base; normal beat
|BBC Research and Development Report Number 1978-25|
R&D Report 1978-25 : Probability levels of sound interference between programme areas. R. Walker Sound insulation must be provided between any two programme areas which are near to or adjacent to each other. For economic reasons, this insulation ideally must be no more than is necessary to reduce the interference from one area to the other to an acceptably low level. To determine the minimum necessary sound insulation requires a knowledge of the maximum sound pressure level on the source side of...
Keywords: noise; interference; background; sound; perceptible; criterion; masking; insulation; levels; level; noise criterion; standard deviation; background noise; noise level; sound pressure; pressure level; receiving area; pressure levels; sound insulation; programme areas
|BBC Research and Development Report Number 1969-51|
R&D Report 1969-51 : Car radio reception tests: Winter 1968/9 C.R.G. Reed, J.G. Spencer During the winter of 1968/9 observations on car radio reception in the UK were made by a number of BBC staff. Questionnaires were completed by 29 participants covering the reception quality of BBC services in the low-frequency (l.f), medium frequency (m.f) and very-high-frequency (v.h.f) bands. Analysis showed that the single l.f transmitter provided a reliable service over most of England and Wales...
Keywords: receiver; reception; radio; interference; signal; frequency; grade; transmitter; car radio; tuning; signal level; service areas; service area; field strength; radio reception; department report; hilly areas; signal strength; noise level
|BBC Research and Development Report Number 1968-08|
R&D Report 1968-08 : The assessment of noise in audio-frequency circuits W.K.E. Geddes Experiments have been carried out to determine the signal-to-noise ratio to be aimed at in programme channels and to compare the methods of noise measurement used or proposed by various broadcasting organisations. First, subjective tests were undertaken to establish the maximum level at which various types of noise can exist in an audio-frequency circuit without producing impairment...
Keywords: noise; meter; noises; weighting; subjective; monophonic; ppm; tests; programme; impulses; listening levels; impulsive noises; white noise; sound level; weighting network; weighting networks; listening room; subjective tests; noise level; studio output
|BBC Research and Development Report Number 1981-01|
R&D Report 1981-01 : Revision of the sound insulation requirements in broadcasting studio centres. R. Walker The BBC sound insulation requirements within studio centres have been based on a report published in 1968. Since that time, there have been new measurements of sound pressure levels in studios, control rooms and other areas, and new background noise level criteria have been proposed for programme areas...
Keywords: insulation; sound; noise; studio; criteria; frequency; pressure; level; criterion; background; insulation requirements; pressure levels; sound pressure; noise level; sound insulation; peak sound; octave band; pressure level; background noise; insulation criteria
|BSTJ 48: 3. March 1969: Apparent Increase in Noise Level When Television Pictures are Frame-Repeated. (Mounts, F.W.; Pearson, D.E.)|
Bell System Technical Journal, 48: 3. March 1969 pp 527-539. Apparent Increase in Noise Level When Television Pictures are Frame-Repeated. (Mounts, F.W.; Pearson, D.E.)
Keywords: noise; interlaced; apparent; picture; repetition; level; attenuator; sequential; ratio; increase; interlaced pictures; interlaced picture; noise level; bell system; apparent increase; noise levels; television pictures; system technical; apparent noise; video signal
|BBC Research and Development Report Number 1978-03|
R&D Report 1978-03 : The masking effect of background noise. A.P.Robinson In some studios, artists have been disturbed by audible breakthrough from adjacent areas, even though the measured sound insulation met the appropriate criterion. This arose because the background noise was quieter than expected, and failed to mask the breakthrough. In the work done, a masking relation, applicable to a studio environment, has been determined by a series of subjective tests...
Keywords: noise; breakthrough; sound; background; band; criterion; critical; masking; octave; bbc; third octave; pop music; background noise; sound insulation; sound pressure; noise level; random noise; pressure levels; critical band; noise band
|Hewlett-Packard Journal Vol. 4 No. 9-10 (1953-06)(Hewlett-Packard)|
Hewlett-Packard Journal Vol. 4 No. 9-10 (1953-06)(Hewlett-Packard)
Keywords: aural; frequency; monitor; meter; visual; carrier; modulation; oscillator; circuit; output; aural carrier; master oscillator; deviation meter; audio output; noise level; difference frequency; pulse counter; visual deviation; visual channel; visual carrier
|BBC Research and Development Report Number 1986-08|
R&D Report 1986-08 : The measurement of large values of airborne sound insulation. R.Walker The requirements for and the measurement of airborne sound insulation between areas in a broadcasting centre are discussed. In particular, the high values of insulation required in some cases and the difficulties of measurement are described. One method which has been used for such measurements, using explosive charges, has been investigated in detail...
Keywords: sound; measurement; insulation; signal; level; noise; frequency; pressure; overload; acoustic; peak sound; octave band; sound pressure; noise level; sound insulation; explosive charges; background noise; pressure levels; pressure level; high sound
|BSTJ 60: 8. October 1981: Improving the Quality of a Noisy Speech Signal. (Sondhi, M.M.; Schmidt, C.E.; Rabiner, L.R.)|
Bell System Technical Journal, 60: 8. October 1981 pp 1847-1859. Improving the Quality of a Noisy Speech Signal. (Sondhi, M.M.; Schmidt, C.E.; Rabiner, L.R.)
Keywords: noise; speech; signal; channel; noisy; estimating; spectral; filter; formant; frequency; isolated channels; impulse response; speech signal; bell system; noisy speech; spectral subtraction; noise estimation; noise level; system technical; channel gains
|BBC Research and Development Report Number 1962-45|
R&D Report 1962-45 : 405-line and 625-line television pictures: The relative impairment produced by random noise. W.K.E. Geddes Subjective assessments have been made, for 405-line and 625-line television pictures, of the impairment produced by addition of random noise to the video signal. It has been found that, for equal impairment, the signal-to-noise ratio must be about 2 dB for a 405 line picture for a 625-line picture.
Keywords: noise; subjective; bandwidth; impairment; ratio; random; attenuator; triangular; flat; television; relative impairment; noise ratio; flat noise; subjective grade; random noise; noise level; predominant source; triangular noise; impairment produced; tests involving
|BSTJ 47: 8. October 1968: The Transmission Performance of Bell System Intertoll Trunks. (Nasell, I.; Ellison, C.R. Jr.; Holmstrom, R.)|
Bell System Technical Journal, 47: 8. October 1968 pp 1561-1613. The Transmission Performance of Bell System Intertoll Trunks. (Nasell, I.; Ellison, C.R. Jr.; Holmstrom, R.)
Keywords: trunks; trunk; toll; intertoll; carrier; facility; frequency; noise; loss; delay; standard deviation; trunk performance; intertoll trunks; trunk length; noise level; voice frequency; office equipment; impulse noise; bell system; toll trunk
|BSTJ 13: 4. October 1934: Fluctuation Noise in Vacuum Tubes. (Pearson, G.L.)|
Bell System Technical Journal, 13: 4. October 1934 pp 634-653. Fluctuation Noise in Vacuum Tubes. (Pearson, G.L.)
Keywords: noise; tube; thermal; vacuum; grid; voltage; tubes; input; frequency; plate; fluctuation noise; vacuum tube; thermal noise; shot noise; thermal agitation; tube noise; noise level; vacuum tubes; space charge; noise voltage
|BBC Research and Development Report Number 1966-29|
R&D Report 1966-29 : Consideration of aircraft noise and studio roof insulation A.N. Burd The increase of noise arising from the widespread use of jet aircraft has led to interference with programme in some broadcasting studios. The actual levels and spectra of noise from aircraft and the distribution of noise levels around a major airport are considered in order to reach a specification for the sound insulation of roofs to exclude such noise.
Keywords: noise; levels; aircraft; roof; studio; octave; sound; insulation; spectra; pndb; pressure levels; sound insulation; noise levels; octave band; sound level; sound pressure; level differences; roof insulation; aircraft noise; noise level
|national :: appNotes :: AN-0390|
From the bitsavers.org collection, a scanned-in computer-related document.national :: appNotes :: AN-0390
Keywords: noise; audio; dnr; frequency; khz; source; level; signal; path; reduction; noise spectrum; noise floor; noise reduction; audio noise; noise level; wiper arm; audio cassette; national semiconductor; control path; field strength
|BBC Research and Development Report Number 1977-33|
R&D Report 1977-33 : New block-codes for digital tape recording. M.E. Bailey This report describes the theoretical and practical performance of certain digital codes potentially suitable for digital sound and television recording on magnetic tape. The adopted criterion of performance is the attainable packing-density of user-data, ie source data, consistent with an adequate bit-error rate. Two particular block-codes were found which provided a 20% increase in the user-data packing-density relati...
Keywords: modulation; data; code; delay; nrz; recording; error; equalisation; codes; coded; error rate; string length; delay modulation; string lengths; data rate; recording channel; replay head; packing density; user data; noise level
|aReW recordings presents [RW-035] Sounds For The Subconcious (various artists)|
aReW recordings netlabel announce release number thirty five (RW-035) available for free mp3 download. A various compilation of experimental, ambient, drone and electronic tracks featuring 13 tracks by 13 artists. The release aReW recordings presents sounds for the subconcious clocks in at 70 minutes approx and features the following artists (in order of appearance): endote, magenta lovecraft, subversive intentions, der domestizierte mensch, trans atlantic rage, balogh, lienullnoyz, noise level,...
Keywords: ambient; experimental; noise; drone; electronic; extrasystole; ReAkshen; feltch; 10Konekt; endote; Magenta Lovecraft; Subversive Intentions; Der Domestizierte Mensch; TRANS ATLANTIC RAGE; BALOGH; lienullnoyz; Noise Level; 30-hcir; aReW recordings
|BBC Research and Development Report 1955-17 : Receiver signal/noise ratio improvement using post detector selectivity - R.V. Harvey|
R&D Report 1955-17 : Receiver signal/noise ratio improvement using post detector selectivity. R.V. Harvey In the design of radio receivers for the measurement of certain types of amplitude-modulated transmission, a useful increase in the output signal/noise ratio can be achieved by restricting the bandwidth after detection. Even when the signal is well below noise level at the detector input, it may be considerably above noise level at the output of the receiver...
Keywords: output; signal; detector; ratio; receiver; bandwidth; input; noise; attenuator; modulated; noise spectrum; noise level; noise factor; ratio improvement; signal output; noise voltage; output spectrum; noise output; power density; linear detector
|BBC Research and Development Report Number 1967-11|
R&D Report 1967-11 : Psychoacoustic criteria for background noise and sound insulation in broadcasting studios C.L.S. Gilford, D.K. Jones This report summarises the criteria at present used to guide the design of studios with respect to background noise and sound insulation. Many of these criteria have been difficult to determine by definitive experiments and have therefore been evolved by experience and indirect methods which are described in this report, together with specifications for measur...
Keywords: noise; sound; studios; studio; ventilation; octave; insulation; levels; specifications; background; sound studios; noise level; background noise; noise levels; sound insulation; ventilation noise; sound level; pressure levels; sound pressure; ventilation system
|BBC Research and Development Report Number 1993-14|
R&D Report 1993-14 : RINSE: a digitally implemented flywheel sync regenerator for improved video synchroniser performance. R.H.Evans Microwave links are widely used at live outside broadcast events for carrying video signals from mobile cameras such as those carried on the shoulder or fitted to vehicles. A digital frame store synchroniser is required when using a remote radio-camera and this has caused additional problems with variable quality signals...
Keywords: sync; rinse; video; noise; syncs; synchronisers; signal; synchroniser; frequency; incoming; noise performance; noise level; video signal; frame store; sync separator; rinse unit; external sync; flywheel sync; incoming video; mixed syncs
|Hewlett-Packard Journal Vol. 20 No. 11 (1969-07)(Hewlett-Packard)|
Hewlett-Packard Journal Vol. 20 No. 11 (1969-07)(Hewlett-Packard)
Keywords: noise; analyzer; phase; audio; digital; output; rms; model; signal; amplitude; noise monitoring; sound level; audio spectrum; aircraft noise; band levels; audio data; data processor; spectrum analyzer; monitoring system; noise level
|BSTJ 18: 4. October 1939: The Computation of the Composite Noise Resulting from Random Variable Sources. (Dietze, E.; Goodale, W.D., Jr.)|
Bell System Technical Journal, 18: 4. October 1939 pp 605-623. The Computation of the Composite Noise Resulting from Random Variable Sources. (Dietze, E.; Goodale, W.D., Jr.)
Keywords: noise; peaks; composite; sound; sources; level; computation; source; observing; average; noise sources; noise level; composite noise; technical journal; sound level; system technical; noise peaks; weight factor; source peaks; bell system
|BSTJ 43: 2. March 1964: The 1962 Survey of Noise and Loss on Toll Connections. (Nasell, Ingemar)|
Bell System Technical Journal, 43: 2. March 1964 pp 697-718. The 1962 Survey of Noise and Loss on Toll Connections. (Nasell, Ingemar)
Keywords: toll; noise; calls; distance; loss; terminating; connection; survey; central; sample; system technical; airline distance; toll calls; noise levels; connection survey; central office; terminating central; bell system; noise level; calls terminating
|BSTJ 13: 4. October 1934: The Measurement and Reduction of Microphonic Noise in Vacuum Tubes. (Penick, D.B.)|
Bell System Technical Journal, 13: 4. October 1934 pp 614-633. The Measurement and Reduction of Microphonic Noise in Vacuum Tubes. (Penick, D.B.)
Keywords: microphonic; tubes; noise; sputter; filament; amplifier; vacuum; tube; levels; mechanical; system technical; noise level; microphonic noise; bell system; vacuum tubes; technical journal; test set; noise levels; sputter noise; microphonic response
|BSTJ 13: 3. July 1934: The Effect of Background Noise in Shared Channel Broadcasting. (Aiken, C.B.)|
Bell System Technical Journal, 13: 3. July 1934 pp 333-350. The Effect of Background Noise in Shared Channel Broadcasting. (Aiken, C.B.)
Keywords: flutter; frequency; carrier; detector; linear; program; ratio; noise; curve; interference; volume control; technical journal; square law; automatic volume; carrier ratio; noise level; linear detector; flutter effects; beat frequency; system technical
|BSTJ : Evaluation of Message Circuit Noise (Aikens, A.J.; Lewinski, D.A.)|
Bell System Technical Journal, 39: 4 July 1960 pp 879-909. Evaluation of Message Circuit Noise (Aikens, A.J.; Lewinski, D.A.)
Keywords: noise; weighting; circuit; transmission; measurement; measuring; weighted; telephone; frequency; message; message circuit; noise measuring; circuit noise; bell system; system technical; noise measurement; measuring set; speech volume; received speech; noise level
|BBC Research and Development Report Number 1970-13|
R&D Report 1970-13 : Acoustic scaling: General outline H.D. Harwood, A.N. Burd An account is given of the possibilities of forecasting the acoustic properties of studios and concert halls by means of small-scale acoustic models. It is shown that the factors involved scale directly with the exception of air absorption and that even this can be made to scale closely if an appropriate degree of humidity is employed...
Keywords: acoustic; frequency; model; studio; reverberation; loudspeakers; ratio; absorption; decay; absorbers; vale studio; sound quality; frequency range; noise level; department report; general outline; resonance frequency; air absorption; decay factor; reverberation time
|Hewlett-Packard Journal Vol. 11 No. 5-7 (1960-01)(Hewlett-Packard)|
Hewlett-Packard Journal Vol. 11 No. 5-7 (1960-01)(Hewlett-Packard)
Keywords: sampling; oscilloscope; signal; pulse; delay; trace; adapter; circuit; probe; instrument; loop gain; sampling system; time scale; time base; random noise; noise level; delay control; voltage samples; voltage accuracy; time delay
|BBC Research and Development Report Number 1980-08|
R&D Report 1980-08 : Revised background noise criteria for broadcasting studios. D.J. Meares, K.F.L. Lansdowne To achieve the correct working conditions in its studios, the BBC has, for many years, specified the maximum level of background noise that can be tolerated. This Report examines the 1968 noise criteria bearing in mind the performance of the current broadcasting network, and concludes that revisions are necessary...
Keywords: noise; studio; studios; acoustic; criteria; sound; ventilation; bbc; criterion; drama; noise level; ventilation noise; background noise; noise criteria; acoustic noise; television studios; noise ratios; sound pressure; noise levels; octave band
|BSTJ 32: 3. May 1953: An Improved Circuit for the Telephone Set. (Bennett, A.F.)|
Bell System Technical Journal, 32: 3. May 1953 pp 611-626. An Improved Circuit for the Telephone Set. (Bennett, A.F.)
Keywords: sidetone; loop; telephone; varistors; impedance; circuit; set; transmitter; resistance; noise; original design; sidetone balance; telephone set; improved circuit; bell system; room noise; noise level; system technical; silicon carbide; received speech
|BSTJ 47: 6. July-August 1968: Some Transmission Characteristics of Bell System Toll Connections. (Nasell, I.)|
Bell System Technical Journal, 47: 6. July-August 1968 pp 1001-1018. Some Transmission Characteristics of Bell System Toll Connections. (Nasell, I.)
Keywords: toll; calls; airline; jitter; noise; survey; transmission; distance; sample; phase; system technical; transmission performance; phase jitter; toll calls; airline distance; noise levels; standard deviation; scatter diagram; bell system; noise level
|73 Magazine (May 1972)|
73 Magazine May 1972 (#140) SSTV Monitor - Built from a kit ...... WA4VAF 17 6 Meter Mobile Transmitter - 40 watts of FM ...... Martens 21 Quick Band Change Mobile Antenna - With output indicator ...... W4LLR 27 Audio IC - For modulators, receivers, etc ...... K1CLL 32 73 Tests the Larsen Antenna - Very effective 5/8 wave mobile FM antenna ...... W2NSD/l 36 How to Get the Stuff into the House - Sneakily ........
Keywords: amateur; frequency; antenna; radio; output; signal; mhz; input; noise; repeater; amateur radio; slow scan; power supply; ham radio; study guide; radio astronomy; vertical sync; radio club; noise level; army mars
|BBC Monograph Number 24|
BBC Monograph 24: The Measurement of Random Noise in the presence of a Television Signal. L.E. Weaver.
Keywords: noise; signal; frequency; ratio; measurement; method; receiver; random; output; spectrum; noise voltage; uniformly illuminated; random noise; television signal; noise power; receiver bandwidth; output signals; noise level; total noise; picture signal
|Roland Juno-106 service notes|
Service notes from the Roland Juno-106 synthesizer. Specifications, block diagram, module board, IC data, panel board, CPU board, module board, bender board, fuse board, power supply board, adjustment procedure. First edition from July 31, 1984. Roland Corporation.
Keywords: test; vcf; cpu; vca; dco; key; board; poly; bender; pwm; jack board; cpu board; slave cpu; oscilloscope test; noise level; module board; midi function; divide data; display window; vcf vca
|fujitsu :: Fujitsu America Computer Products Reference Guide 1990|
From the bitsavers.org collection, a scanned-in computer-related document.fujitsu :: Fujitsu America Computer Products Reference Guide 1990
Keywords: ibm; specifications; interface; capacity; cps; paper; dimensions; color; epson; fujitsu; time track; recording code; transfer rate; paper handling; data transfer; track capacity; noise level; printing speed; positioning time; paper sizes
|Korg Mono-Poly Service Notes|
Keywords: vco; vcf; adjustment; trig; gno; vca; resonance; adjust; gnd; confirm; metal fitting; kbd track; noise level; sensitivity adjustment; radiation board; tact board; specifications parts; phone jack; parts code; noise gain
Downloads: 472 (1 review)
|BSTJ 18: 3. July 1939: The Application of Negative Feedback to Frequency-Modulation Systems. (Chaffee, J.G.)|
Bell System Technical Journal, 18: 3. July 1939 pp 404-437. The Application of Negative Feedback to Frequency-Modulation Systems. (Chaffee, J.G.)
Keywords: feedback; modulation; frequency; output; amplitude; wave; signal; noise; system; disturbance; signal level; modulation level; negative feedback; noise level; technical journal; local oscillator; feedback system; bell system; system technical; output noise
|national :: appNotes :: AN-0384|
From the bitsavers.org collection, a scanned-in computer-related document.national :: appNotes :: AN-0384
Keywords: noise; audio; frequency; khz; signal; masking; dnr; bandwidth; filter; reduction; noise spectra; audio bandwidth; noise reduction; noise level; control path; audible noise; pass filter; national semiconductor; low pass; program material
|BBC Monograph Number 44|
BBC Monograph 44: A Band V Signal-frequency Unit and a Correlation Detector for a VHF/UHF Field-strength Recording Receiver. G.J. Phillips, P.T.W. Vance, R.V. Harvey.
Keywords: output; detector; frequency; signal; circuit; noise; receiver; band; oscillator; input; resonant filter; original band; correlation detector; local oscillator; recording receiver; bbc engineering; final multiplier; schematic diagram; noise factor; noise level
|BSTJ 14: 1. January 1935: Limits to Amplification. (Johnson, J.B.; Llewellyn, F.B.)|
Bell System Technical Journal, 14: 1. January 1935 pp 85-96. Limits to Amplification. (Johnson, J.B.; Llewellyn, F.B.)
Keywords: noise; thermal; amplifier; input; voltage; ratio; frequency; tube; tubes; cathode; technical journal; system technical; thermal noise; thermal agitation; space charge; radio frequency; noise voltage; noise level; input circuit; bell system
|BBC Research and Development Report Number 1980-15|
R&D Report 1980-15 : Digital sound: studio signal coding resolution for broadcasting. W.I. Manson The standards of coding accuracy appropriate for a pulse-code-modulation (p.c.m) system distributing high-quality sound-programme signals are now relatively well established. In this application the analogue signals are controlled in level before coding, and experience has shown that a 13 to 14 bits/sample system, with pre- and de-emphasis, provides a performance appropriate for high-quality radio b...
Keywords: noise; coding; signal; digital; signals; bbc; analogue; microphone; distortion; granular; sound signals; microphone noise; granular distortion; noise level; coding resolution; microphone output; noise criteria; signal level; acoustic noise; studio noise
|BBC Research and Development Report Number 1984-07|
R&D Report 1984-07 : Video noise reduction J.O. Drewery, R. Storey, N.E. Tanton A video noise and film grain reducer is described which is based on a first-order recursive temporal filter. Filtering of moving detail is avoided by inhibiting recursion in response to the amount of motion in a picture. Motion detection is based on the point-by-point power of the picture difference signal coupled with a knowledge of the noise statistics...
Keywords: noise; filter; picture; spatial; signal; pulse; input; output; frequency; threshold; noise measurement; block diagram; noise reduction; filter output; spatial filter; probability distribution; motion detector; noise level; picture difference; shot change
|BBC Research and Development Report Number 1987-20|
R&D Report 1987-20 : The assessment of the sound insulation requirements for a large broadcasting studio, using a scale model: Theoretical considerations. E.W. Taylor The theory of sound transmission into a reverberant enclosure is discussed, particularly for the cases where more than one transmitting panel is involved, and where the source sound field may be either reverberant or direct. The coherence properties of road traffic noise and filtered white noise are also examined, and the implicati...
Keywords: sound; equation; noise; surface; energy; reflecting; transmission; pressure; level; density; traffic noise; sound pressures; sound pressure; sound field; pressure level; reflecting surface; noise level; potential energy; energy density; normal incidence
|BSTJ : Frequency Shift Telegraphy -- Radio and Wire Applications (Davey, J.R.; Matte, A.L.)|
Bell System Technical Journal, 27: 2 April 1948 pp 265-304. Frequency Shift Telegraphy -- Radio and Wire Applications (Davey, J.R.; Matte, A.L.)
Keywords: frequency; amplitude; noise; discriminator; shift; signal; distortion; band; diversity; phase; frequency shift; shift telegraphy; frequency drift; technical journal; system technical; bell system; phase modulation; noise level; linear discriminator; band width